Fast and Ultraclean Approach for Measuring the Transport Properties of Carbon Nanotubes

In this work, a fast approach for the fabrication of hundreds of ultraclean field-effect transistors (FETs) is introduced, using single-walled carbon nanotubes (SWCNTs). The synthesis of the nanomaterial is performed by floating-catalyst chemical vapor deposition, which is employed to fabricate high-performance thin-film transistors. Combined with palladium metal bottom contacts, the transport properties of individual SWCNTs are directly unveiled. The resulting SWCNT-based FETs exhibit a mean field-effect mobility, which is 3.3 times higher than that of high-quality solution-processed CNTs. This demonstrates that the hereby used SWCNTs are superior to comparable materials in terms of their transport properties. In particular, the on–off current ratios reach over 30 million. Thus, this method enables a fast, detailed, and reliable characterization of intrinsic properties of nanomaterials. The obtained ultraclean SWCNT-based FETs shed light on further study of contamination-free SWCNTs on various metal contacts and substrates.